There have conventionally been proposed many apparatuses that achieve washing by exploiting ultrasonic waves. Japanese Patent Applications Laid-Open Nos. 2001-310094 and 2001-310165 disclose handy ultrasonic washing apparatuses. These apparatuses have an ultrasonic horn joined to an ultrasonic vibrator housed in a hand-held casing, and achieve washing with the tip of the ultrasonic horn kept in contact with an article to be cleaned that has been soaked in washing liquid so as to be imbued therewith. The power source is a battery housed in the casing.
These conventional ultrasonic washing apparatuses boast their compactness and light weight, and accordingly produce a rather low output of ultrasonic vibration. Thus, to obtain a satisfactory washing effect, they need to be passed over and over across the article to be cleaned. Compact and lightweight as these apparatuses are, repeating such operation causes fatigue in the user's hand. Moreover, since the user needs to use one hand to hold the ultrasonic washing apparatus, he or she needs to hold the article to be cleaned with the other hand alone. This makes it impossible to hold the article tense, resulting in wrinkles and twists developing therein as the ultrasonic washing apparatus is passed across it. With wrinkles or twists in the article, the ultrasonic horn cannot be kept in optimal contact with the article. This not only hampers obtaining the expected washing effect, but also tends to result in the article being cleaned unevenly or imperfectly in wrinkled or twisted parts thereof.